Seventh Circle Audio

I'm getting a hum with all of my sea preamps when connected to a Midas venice Console. I'm not sure what the issue could be - the sound is around 50-80hz and I've tried different power supplies a power conditioner, the insert, the line in.... what could be the issue?

Disconnect everything except the console and the preamp chassis. Plug them into the same outlet. Monitor through the console headphone output. What happens?

That worked - no more hum. What could of caused that? A ground loop from some other effect unit? Thanks!!!

A ground loop from some other effect unit?

Probably. Cable boxes, modems, and other equipment that connects to ground via another route than the AC wiring are the worst culprits. Add your other boxes to the setup one at a time until you find the offending unit.